Research On Epi-fluorescence Detection Technique For Microfluidic Chips

Microfluidic chip technique has some successful applications in biochemicalanalysis area such as DNA sequencing, separation and analysis for protein andmonoplast, etc. Comparing with traditional capillary electrophoresis (CE), it has manypotential advantages such as high efficiency, high speed, less reagent consume, highreliability and so on. The signal detection technique of microfluidic chips is alwaysthe emphasis and the difficulty for the researches and applications of microfluidicchips. The dissertation work is a research topic for signal detection technique ofmicrofluidic chips, an epi-fluorescence detecting device was designed and made out,then detections of Rhodamine B and Fluorescein were completed with the device.The experiment results showed that the device has certain sensitivity, good linearityand repeatability. In this paper, the research work includes following aspects:1. According to the references both here and abroad, the different factors thataffect the whole performance of the detection system have been analyzed, the systemwas constructed with an epi-fluorescence detection system while the light path withinhas a special design called "light trap".2. The detected fluorescent data acquisition and processing system has beendesigned and fabricated. The fluorescence signal is collected by the microscopicalobject lens and converted to electronic signal by photodiode,finally the signal issampled and dealt with by the following circuits ,and the functions of dataacquisition,transmission and display in time were completed.3. The experimental verification was accomplished.The whole system wassuccessfully applied to detect the fluorescent dye: Rhodamine B and Fluorescein,with certain sensitivity and linearity. The "light trap" structure has proved effective inreducing the background noise to some extent.The dissertation work accomplished some explorings for design anddevelopment of detecting system for microfluidic chips,the epi-fluorescencedetecting idea was proposed,optical,electronic and software systems were designedand developed. This work was meritorious for microfluidic detection technology.